BoilerFaultCodesTechnical description
Indicates that the pilot light is not operating correctly, or the combustion products discharge safety device has been activated (lockout).
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the pilot flame has gone out or that dangerous exhaust gases are not leaving the flue correctly. The most common reason is a worn-out sensor failing to detect the flame, though it can also be triggered if a blockage in the chimney or wind gust disrupts the burner.
This issue often appears during the first cold snap of autumn when the boiler is pushed to run for longer periods after being idle all summer.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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